Formation of particulate-phase and gas-phase polycyclic aromatic hydrocarbons in cigarette smoke

This study examines the concentrations of particulate-phase polycyclic aromatic hydrocarbons (PAHs) and gas-phase PAHs in sidestream cigarette smoke. Sixteen PAHs were determined for four brands of cigarettes. The volume of the experimental room is approximately 66 m3. The air samples in the room were collected before and after smoking. The median total of particulate-phase and gas-phase PAH concentrations before smoking 3.13 ng/m3 and 48.0 ng/m3, respectively. The median concentrations of them after smoking were 10.0 ng/m3 and 79.6 ng/m3. The median increases in the total of 16 PAH concentrations per cigarette during smoking were 271 ng for the particulate-phase PAHs and 1960 ng for the gas-phase PAHs. According to the relationship between particulate-phase and gas-phase PAHs after smoking, the two- to four-ring gas-phase PAHs and the higher molecular weight particulate-phase PAHs were probably formed from similar precursors. The relationship between the total suspended particulate (TSP) concentration and the increase in the total particulate-phase concentration of the 16 PAHs per cigarette during smoking were significantly positive. The increase in the total gas-phase concentration of the 16 PAHs tended to increase as the TSP concentration increased. This may indicates that decreasing the amount of TSP produced inhibit the production of PAHs during smoking.